package cn.sn.utils;

import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * IpUtils
 *
 * @author liliudong
 * @version 1.0
 * @description
 * @date 2023/7/26 19:14
 */
@Component
@RequiredArgsConstructor
@Slf4j
public  class IpUtils {

    private final HttpServletRequest request;

    private final static String UNKNOWN = "unknown";
    private final static String LOCAL_HOST_IP = "127.0.0.1";
    private final static String LOCAL_HOST_ADDR = "0:0:0:0:0:0:0:1";

    public  String getClientIp() {

        String ipAddress = request.getHeader("X-Forwarded-For");

        if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("Proxy-Client-IP");
        }

        if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("WL-Proxy-Client-IP");
        }

        if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getRemoteAddr();
            if (LOCAL_HOST_IP.equals(ipAddress) || LOCAL_HOST_ADDR.equals(ipAddress)) {
                // 根据网卡取本机配置的IP
                InetAddress inet = null;
                try {
                    inet = InetAddress.getLocalHost();
                } catch (UnknownHostException e) {
                    log.error("----无法获取登录人的IP地址----");
                    return "";
                }
                assert inet != null;
                ipAddress = inet.getHostAddress();
            }
        }

        // 对于通过多个代理的情况，第一个IP为客户端真实IP，多个IP按照','分割
        if (ipAddress != null && ipAddress.length() > 15) {
            if (ipAddress.indexOf(",") > 0) {
                ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
            }
        }

        return ipAddress;
    }

}
